Performance analysis of a hybrid RF/FSO comunication system with QKD for ventilation monitoring

This work proposes a hybrid communication system to relay, send and visualize data in real time by integrating respective technologies to RF and FSO channels for ventilation monitoring systems. The RF network uses Long Range Wide Area Network (LoRaWAN) communication protocols, ideal for long distance connections and for IoT networks where sensors with coverage between 100 m and 1 m without line of sight and with line of sight between 10 km and 20 km are needed, On the other hand there is an infrared (IR) Free Space Optical (FSO) laser communication link that operates as a network data concentrator and can send data at high transmission rates in the order of Gbps, being able to operate in the THz spectrum bands (~1012 GHz) without a license (wavelength 800–1700 nm), Thus, by using metrics such as Received Signal Strength Indicator (RSSI), Signal to Noise Ratio (SNR) and Bit Error Rate (BER) of the proposed system, the performance of the Free Space Path Loss (FSPL) models using the “rational function” algorithm is compared with respect to the analytical Free Space Path Loss model and the empirical Oulo Path Loss model reaching a model. Studies have also been carried out on the Advanced Encryption Standard (AES) with Quantum Key Distribution (QKD) to provide security in links such as the FSO laser, which uses TCP/IP connection.